New pitbull pup almost bites my face! : (?

My husband and I got a puppy three days ago. We are already in LOVE with him. He's such a good boy, licks my kids like crazy, already almost housebroken.. sleeps in his crate at night, comes when we call him. Hasen't chewed up anything. He is a pitbull pup and he's 3 months old. We have two children and one on the way.. I have read a TON it seems on the breed and my husband loves the breed so much. Well Tito and I have been sitting on the couch for a few hours.. he's been sleeping, we've been cuddling. Sweet. Well I was holding him and kissing his face when he started growling. I said "What's wrong, boy?!" He growled again and snapped into my face like trying to bite me in the face. I have NO idea where that came from. I called my husband in here almost in tears bc it took me by such surprise. My husband guessed maybe I was hurting him somehow.. I guessed maybe he had to pee bc he just woke from a nap and I was holding him. (?!) My husband let him out and now he's right here back with me on the couch laying beside me like nothing happened. What in the heck? Will he do this again? I'm thinking if he did that to me, my kids will DEF do something at one point or another. I am confused. I already feel that I love his personality and everything. I'm so upset!! Advice please?!